The invention relates to a two gear train reduction mechanism, in particular for the programmer of a domestic washing machine, in which a reversing cam, for actuating reversing contacts, is rotated by a motor over a predetermined angular space and through a first reduction gear train whose speed reduction is compatible with the proper operation of the reversing contacts, the cam being further rotated over the rest of its revolution by same motor through a second reduction gear train of a different speed reduction, so that the total duration of the revolution of the cam be that selected for the cycle of a periodical phenomenon programmed by said cam.
A reduction mechanism having two gear trains of different speed reductions is already indicated by the U.S. Pat. No. 378,240. But these two gear trains are not provided for engaging alternately a single cam. On the contrary, they engage two different cams, respectively, the second gear train engaging constantly the second cam.
Moreover a several gear train reduction mechanism is indicated by the British Patent No. 929,461, which is provided for engaging a single cam through a single step-up gear engaging alternately either of the gear trains, said step-up gear being mounted on a pivotable lever.
Finally, such a mechanism including an uncoupling spring mounted in a way to act suddenly is indicated by the French Patent No. 942,316.